Aluminum electrolytic tank anode carbon block of irregularly-shaped structure with exhaust passage and preparation method thereof

ABSTRACT

An aluminum electrolytic tank anode carbon block characterized by edges of top surface carbon block are provided with chamfers, a row or two rows of carbon bowls are uniformly distributed on the top surface. Each row of carbon bowls are longitudinally arranged along the anode carbon block and consist of 3 to 5 carbon bowls. Grooves are formed among the carbon bowls, the bottom of the anode carbon block is provided with trenches, and the bottom of each groove is provided, with through holes which are in communication with the trenches. The preparation method includes: preparing the carbon block by using a vibration mold or compression mold with corresponding bumps by a vibration molding method or a compression molding method; and roasting and then cutting out the trenches. The anode carbon block has the characteristics of a simple and convenient preparation process, high working efficiency and the like.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention belongs to the technical field of aluminum electrolysis, in particular relates to an aluminum electrolytic tank anode carbon block of an irregularly-shaped structure with an exhaust passage and a preparation method thereof.

2. The Prior Arts

For an industrial aluminum electrolytic tank, there are two important technical economical indices, i.e. current efficiency and DC power consumption. The two indices have different concepts, but have a close relation. The relation between the current efficiency CE (%) and the DC power consumption W (kWh/t-Al) of aluminum electrolysis can be presented by the following formula:

W=2980×(V _(avg) /CE)   (1)

Where: V_(avg) is the average tank voltage of aluminum electrolysis. As can be seen from this formula, when the current efficiency of the electrolytic tank is increased by 1%, the DC power consumption can be reduced by about 150 kWh/t-Al, and the yield of aluminum can be increased by 1% at the same time; when the tank voltage is reduced by 0.1 V, the DC power consumption can be reduced by about 300 kWh/t-Al.

It is well known that the reduction of current efficiency in the aluminum electrolytic tank is caused by the so-called secondary reaction of aluminum between the aluminum dissolved in the molten electrolyte and the CO₂ produced and discharged by the anode, this means that when the anode of the electrolytic tank is larger, the course for the anodic gas to be discharged from the bottom of the anode and escape from the surface of the electrolyte is longer, the times of the secondary reaction of the aluminum in the molten electrolyte is more, and the loss of current efficiency is higher. Therefore, if the CO₂ produced on the bottom surface of the anode in the aluminum electrolytic tank can escape from the bottom surface of the anode faster to shorten the residence time of CO₂ in the electrolyte, the current efficiency of the aluminum electrolytic tank can be increased greatly.

Based on the above theory, American invented an electrolytic tank anode technology which has two trenches cut out upwards from the bottom surface of the anode in the longitudinal direction of the electrolytic tank, aiming at enabling part of the anodic gas produced on the bottom of the electrolytic tank anode to escape from the trenches so as to achieve the purpose of reducing the secondary reaction between anodic gas and aluminum, and the depth of the trenches in the bottom of the electrolytic tank anode is 200 to 250 mm. However, since such trenches are too shallow, the trenches are immersed in the molten electrolyte during most of the working hours of the anode, causing no shortening in the residence time of the anodic gas in the molten electrolyte and no reduction in the resistance of the anodic gas, therefore, the effect of this technology on increasing the current efficiency or reducing the power consumption of the electrolytic tank is not obvious.

Thereafter, in order to improve this situation, people invented aluminum electrolytic tank anode technologies of other structures, including an aluminum electrolytic tank anode technology invented by Li Jie, et al. using one anode rod, four steel claws and four small anodes, and the patent technology invented by Feng Naixiang and Peng Jianping using one anode rod, eight steel claws and more than four small anodes. If these patent technologies can be implemented in industry, they will certainly increase the discharge velocity of anodic gas and increase the current efficiency of electrolytic tank; however, it is found during practical operation that such technology of individual small anodes used on electrolytic tank is easy to cause anode falling off due to the fact that no expansive force used for supporting the anode carbon bowls as a transverse acting force is produced by the transverse beam on the anode steel claws in the condition of high temperature on the top surface of the electrolytic tank. Therefore, to develop a technology which is favorable for quickly discharging gas at anode is an urgent issue that calls for an immediate solution at present.

SUMMARY OF THE INVENTION

In consideration of the above issues on gas discharge of the existing aluminum electrolytic tank anode, the present invention provides an aluminum electrolytic tank anode carbon block of an irregularly-shaped structure with an exhaust passage and a preparation method thereof. By forming grooves among carbon bowls on an individual anode carbon block of a carbon anode and making the grooves be in communication with the trenches in the bottom of the anode carbon block via through holes, the present invention makes the gas produced by the anode during the operation of the anode carbon block discharged smoothly and uniformly and reduces the influence of gas escape from the electrolyte on fluctuation of cathode molten aluminum, which can not only prevent the anode from falling off, but also enable the gas to be discharged quickly from the bottom surface of the anode.

The edges of the top surface of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of the present invention are provided with chamfers, a row or two rows of carbon bowls are uniformly distributed on the top surface, and each row of carbon bowls are longitudinally arranged along the anode carbon block and consist of 3 to 5 carbon bowls. Grooves are formed among the carbon bowls, and the bottom of the anode carbon block is provided with trenches. The bottom of each groove is provided with through holes which are in communication with the trenches in the bottom of the anode carbon block.

In the anode carbon block, when a row of carbon bowls are arranged on the top surface of the anode carbon block, a transverse groove is formed between every two adjacent carbon bowls; when two rows of carbon bowls are arranged on the top surface of the anode carbon block, a longitudinal groove is formed between the two rows of carbon bowls, or a transverse groove is formed between every two adjacent carbon bowls in the same row and a longitudinal groove is formed between the two rows of carbon bowls; when both the transverse grooves and the longitudinal groove are formed, the transverse grooves are in communication with the longitudinal groove.

The trenches are in the bottom of the anode carbon block in positions corresponding to each groove. The bottom of each grove is provided with at least one through hole which is in communication with the trench corresponding to this groove.

The axis of the transverse groove is vertical to the longitudinal axis of the anode carbon block, the axis of the transverse groove is in the middle of two adjacent carbon bowls, and both ends of the transverse groove extend to the chamfers of two long edges. The axis of the longitudinal groove runs parallel to the axis of the anode carbon block. The longitudinal groove is in the middle of two adjacent rows of carbon bowls, and both ends of the longitudinal groove extend to the chamfers of two short edges.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the bottom of each trench is in communication with the bottom surface of the anode carbon block. The trenches corresponding to the transverse grooves are transverse trenches, and the trench corresponding to the longitudinal groove is a longitudinal trench. The length of each transverse trench is equal to the width of the anode carbon block, the length of the longitudinal trench is equal to the length of the anode carbon block, and the width of each trench is 1.0 to 3.5 cm.

The cross section of each groove is an inverted isosceles triangle or an inverted isosceles trapezoid, and the height of each groove is 3 to 10 cm. When the cross section of each groove is an inverted isosceles triangle, the width of the top surface of each groove is 3 to 10 cm. When the cross section of each groove is an inverted isosceles trapezoid, the width of the top surface of each groove is 5 to 10 cm, and the width of the bottom surface is 3 to 8 cm.

The through holes are in the bottom of the grooves, and the longitudinal axis of each through hole is vertical to the bottom surface of the anode carbon block,

The through holes include small through holes and large through holes. The cross section of each small through hole is circular, oval, square or rectangular, with an area of 3 to 18 cm². When the cross section of the small through hole is square or rectangular, four corners of the square or rectangle are filleted corners. The cross section of each large through hole is rectangular, with an area of 18 to 500 cm².

In the anode carbon block, when the length of each through hole is equal to the length of the anode carbon block, the through holes are in communication with the trenches, and one anode carbon block is longitudinally divided into two identical small anode carbon blocks.

The aluminum electrolytic tank carbon anode of the irregularly-shaped structure with the exhaust passage of the present invention is composed of more than 20 individual anode carbon blocks of the irregularly-shaped structure, and the preparation method for each anode carbon block comprises:

Preparing a green body of the anode carbon block by a vibration molding method or a compression molding method; when the vibration molding method is used, the lower surface of the upper weight dropper in a vibration mold is provided with corresponding bumps; when the compression molding method is used, the lower surface of the upper mold core in a compression mold is provided with corresponding bumps; preparing carbon bowls, grooves and deep holes with a depth of 20 to 50 cm in the green body of the anode carbon block during vibration molding or compression molding; after demolding and cooling down, putting the green body of the anode carbon block into a roasting furnace and roasting to 1100 to 1300° C. to prepare a roasted body of the anode carbon block with carbon bowls, deep holes and grooves in the top; and physically cutting out the trenches in the bottom of the roasted body of the anode carbon block and making the trenches be in communication with the deep holes or a groove-shaped passage to form the through holes, thus the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is prepared. The corresponding bumps refer to the bump structures corresponding to the positions of the carbon bowls, grooves and through holes in the anode carbon block.

The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of the present invention is provided with cover plates above the grooves before use. Each transverse groove is provided with a transverse cover plate. The transverse cover plates are covered on the transverse grooves, and the length of each transverse cover plate is equal to the width of the anode carbon block. The longitudinal groove is provided with a longitudinal cover plate. The longitudinal cover plate in covered on the longitudinal groove, and the length of the longitudinal cover plate is equal to the length of the anode carbon block. When the inorganic material and the longitudinal cover plate are covered on the anode carbon block at the same time, the longitudinal cover plate is connected with the transverse cover plates to form an integrated structure, and the cover plates are covered with cryolite powder and then assembled on anode claws of the aluminum electrolytic tank.

The cover plates are made of carbon material, inorganic material or metal. The selected inorganic material may be fireproof material plate or flame-retardant fiber board, and the selected metal may be aluminum plate or iron plate. When carbon block, fireproof material plate or flame-retardant fiber board is selected, the thickness of the cover plate is 5 to 20 cm; when aluminum plate or iron plate is selected, the thickness of the aluminum plate or iron plate is 1 to 4 mm; when iron plate is selected, the iron plate may be provided with holes, and an iron pipe whose upper end is higher than the electrolyte and alumina insulation material covered on the top surface of the anode is welded on each hole to be more favorable for exhausting anodic gas from the tank.

The working principle of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of the present invention is as follows: during aluminum electrolysis, most of the CO₂ produced on the bottom surface of the anode carbon block rises up through the trenches and enters the through holes, then converges in the grooves in the top surface of the anode carbon block from the through holes, enters the cavity between the cover plates and the grooves, and is finally exhausted to the outside of the anode carbon block from the cavity through the iron pipes on the end part or the top of the cover plates.

The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of the present invention has the characteristics of a simple and convenient preparation process, high working efficiency and the like. Besides, it is proved by testing that the tank voltage can be reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, the present invention is favorable for increasing the current efficiency, and falling off phenomena of small anode carbon blocks is avoided, therefore, the present invention has great application prospect.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment thereof, with reference to the attached drawings, in which:

FIG. 1 is the sectional structure diagram of a single aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 1 of the present invention.

FIG. 2 is the A-A sectional view of FIG. 1.

FIG. 3 is the B-B sectional view of FIG. 1.

FIG. 4 is the C-C sectional view of FIG. 1.

FIG. 5 is the D-D sectional view of FIG. 1.

FIG. 6 is the E-E sectional view of FIG. 1.

FIG. 7 is the sectional structure diagram of a single aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 2 of the present invention.

FIG. 8 is the A-A sectional view of FIG. 7.

FIG. 9 is the B-B sectional view of FIG. 7.

FIG. 10 is the C-C sectional view of FIG. 7.

FIG. 11 is the D-D sectional view of FIG. 7.

FIG. 12 is the E-E sectional view of FIG. 7.

FIG. 13 is the sectional structure diagram of the aluminum electrolytic tank anode Carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 3 of the present invention.

FIG. 14 is the A-A sectional view of FIG. 13.

FIG. 15 is the B-B sectional view of FIG. 13.

FIG. 16 is the C-C sectional view of FIG. 13.

FIG. 17 is the D-D sectional view of FIG. 13.

FIG. 18 is the E-E sectional view of FIG. 13.

FIG. 19 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 4 of the present invention.

FIG. 20 is the A-A sectional view of FIG. 19.

FIG. 21 is the B-B sectional view of FIG. 19.

FIG. 22 is the C-C sectional view of FIG. 19.

FIG. 23 is the D-D sectional view of FIG. 19.

FIG. 24 is the E-E sectional view of FIG. 19.

FIG. 25 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 5 of the present invention.

FIG. 26 is the A-A sectional view of FIG. 25.

FIG. 27 is the B-B sectional view of FIG. 25.

FIG. 28 is the C-C sectional view of FIG. 25.

FIG. 29 is the D-D sectional view of FIG. 25.

FIG. 30 is the E-E sectional view of FIG. 25.

FIG. 31 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 6 of the present invention.

FIG. 32 is the A-A sectional view of FIG. 31.

FIG. 33 is the B-B sectional view of FIG. 31.

FIG. 34 is the C-C sectional view of FIG. 31.

FIG. 35 is the D-D sectional view of FIG. 31.

FIG. 36 is the E-E sectional view of FIG. 31.

FIG. 37 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 7 of the present invention.

FIG. 38 is the A-A sectional view of FIG. 37.

FIG. 39 is the B-B sectional view of FIG. 37.

FIG. 40 is the C-C sectional view of FIG. 37.

FIG. 41 is the D-D sectional view of FIG. 37.

FIG. 42 is the E-E sectional view of FIG. 37.

FIG. 43 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 8 of the present invention.

FIG. 44 is the A-A sectional view of FIG. 43.

FIG. 45 is the B-B sectional view of FIG. 43.

FIG. 46 is the C-C sectional view of FIG. 43.

FIG. 47 is the D-D sectional view of FIG. 43.

FIG. 48 is the E-E sectional view of FIG. 43.

FIG. 49 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 9 of the present invention.

FIG. 50 is the A-A sectional view of FIG. 49.

FIG. 51 is the B-B sectional view of FIG. 49.

FIG. 52 is the C-C sectional view of FIG. 49.

FIG. 53 is the D-D sectional view of FIG. 49.

FIG. 54 is the E-E sectional view of FIG. 49.

FIG. 55 is the sectional structure diagram of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage in Embodiment 10 of the present invention.

FIG. 56 is the A-A sectional view of FIG. 55.

FIG. 57 is the C-C sectional view of FIG. 55.

The figures respectively show anode carbon block 1, carbon bowl 2, groove 3, through hole 4, trench 5 and cover plate 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The inner diameter of each carbon bowl in the embodiments of the present invention is 100 to 250 mm, and the depth is 100 to 200 mm.

Embodiment 1

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 1, the A-A sectional structure is shown in FIG. 2, the B-B sectional structure is shown in FIG. 3, the C-C sectional structure is shown in FIG. 4, the D-D sectional structure is shown in FIG. 5, and the E-E sectional structure is shown in FIG. 6. The edges of the top surface of the anode carbon block 1 are provided with chamfers, two rows of carbon bowls are uniformly distributed on the top surface, and each row of carbon bowls are longitudinally arranged along the anode carbon block and consist of four carbon bowls 2. Grooves 3 are formed among the carbon bowls, and the bottom of each groove is provided with through holes 4 which are in communication with trenches 5 in the bottom of the anode carbon block. Cover plates 6 are arranged above the grooves.

A transverse groove is formed between every two adjacent carbon bowls in the same row, a longitudinal groove is formed between the two rows of carbon bowls, and the transverse grooves are in communication with the longitudinal groove.

The trenches are formed in the bottom of the anode carbon block in positions corresponding to each groove. The bottom of each groove is provided with three through holes which are in communication with the trench corresponding to this groove.

The axis of each transverse groove is vertical to the longitudinal axis of the anode carbon block, the axis of each transverse groove is in the middle of two adjacent carbon bowls, and both ends of each transverse groove extend to the chamfers of two long edges. The axis of the longitudinal groove runs parallel to the axis of the anode carbon block. The longitudinal groove is in the middle of two adjacent rows of carbon bowls, and both ends of the longitudinal groove extend to the chamfers of two short edges.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the bottom of each trench is in communication with the bottom surface of the anode carbon block. The trenches corresponding to the transverse grooves are transverse trenches, and the trench corresponding to the longitudinal groove is a longitudinal trench. The length of each transverse trench is equal to the width of the anode carbon block, the length of the longitudinal trench is equal to the length of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, the height of each groove is 3 to 10 cm, and the width of the top surface of each groove is 3 to 10 cm.

The longitudinal axis of each through hole is vertical to the bottom surface of the anode carbon block.

The through holes are small through holes, and the cross section of each through hole is a rectangle with four filleted corners and an area of 10 cm².

The preparation method comprises:

Preparing a green body of the anode carbon block by a vibration molding method, the lower surface of the weight dropper above the carbon paste in a vibration mold is provided with corresponding bumps, and the corresponding bumps refer to the bump structures corresponding to the positions of the carbon bowls, grooves and deep holes in the anode carbon block; preparing carbon bowls, grooves and deep holes with a depth of 20 to 50 cm in the green body of the anode carbon block during vibration molding; putting the demolded green body of the anode carbon block into a roasting furnace and roasting to 1100 to 1300° C. to prepare a roasted body of the anode carbon block with carbon bowls, grooves and deep holes; and then physically cutting out the trenches in the bottom of the roasted body of the anode carbon block and making the trenches be in communication with the deep holes to form the through holes, thus the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is prepared.

The prepared grooves are provided with cover plates. The cover plates are covered above the grooves and integrated with the carbon block, and a porous channel with a triangular cross section is formed between each cover plate and each groove.

It is proved by testing that the tank voltage can be reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 2

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 7, the A-A sectional structure is shown in FIG. 8, the B-B sectional structure is shown in FIG. 9, the C-C sectional structure is shown in FIG. 10, the D-D sectional structure is shown in FIG. 11, and the E-E sectional structure is shown in FIG. 12. The edges of the top surface of the anode carbon block 1 are provided with chamfers, a row of carbon bowls are uniformly distributed on the top surface along the longitudinal direction of the anode carbon block, and the row of carbon bowls consist of four carbon bowls 2. Grooves 3 are formed among the carbon bowls, and the bottom of each groove is provided with through holes 4 which are in communication with trenches 5 in the bottom of the anode carbon block. Cover plates 6 are arranged above the grooves.

A transverse groove is formed between every two adjacent carbon bowls. The trenches are formed in the bottom of the anode carbon block in positions corresponding to each groove. The bottom of each groove is provided with seven through holes which are in communication with the trench corresponding to this groove.

The axis of each transverse groove is vertical to the longitudinal axis of the anode carbon block, the axis of each transverse groove is in the middle of two adjacent carbon bowls, and both ends of each transverse groove extend to the chamfers of two long edges.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, the bottom of each trench is in communication with the bottom of the anode carbon block, the length of the each trench is equal to the width of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, and the height of each groove is 3 to 10 cm. The width of the top surface of each groove is 3 to 10 cm.

The longitudinal axis of each through hole is vertical to the bottom surface of the anode carbon block.

The through holes are small through holes, and the cross section of each through hole is a rectangle with four filleted corners and an area of 12 cm².

The preparation method comprises:

Preparing a carbon block by a compression molding method, the lower surface of the upper mold core in a compression mold is provided with corresponding bumps; preparing carbon bowls, grooves and deep holes with a depth of 20 to 50 cm in the green body of the anode carbon block during compression molding; other steps are the same as those of Embodiment 1.

The grooves are provided with transverse cover plates.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 3

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 13, the A-A sectional structure is shown in FIG. 14, the B-B sectional structure is shown in FIG. 15, the C-C sectional structure is shown in FIG. 16, the D-D sectional structure is shown in FIG. 17, and the E-E sectional structure is shown in FIG. 18. The structure is the same as that of Embodiment 1, but the difference is that: Each transverse groove is provided with two through holes in communication with the corresponding trench, and the longitudinal groove is provided with one through hole in communication with the corresponding trench.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, the height of each groove is 3 to 10 cm, and the width of the top surface of each groove is 3 to 10 cm.

The through holes are large through holes, the section of each through hole is a rectangle, the cross section area of the two through hole in each transverse groove is 50 cm², and the cross section area of the through hole in the longitudinal groove is 390 cm².

The preparation method is the same as that for Embodiment 1.

The grooves are provided with cover plates by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 4

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 19, the A-A sectional structure is shown in FIG. 20, the B-B sectional structure is shown in FIG. 21, the C-C sectional structure is shown in FIG. 22, the D-D sectional structure is shown in FIG. 23, and the E-E sectional structure is shown in FIG. 24. The structure is the same as that of Embodiment 1, but the difference is that: The bottom of each groove is provided with one through hole which is in communication with the trench corresponding to this groove.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, the height of each groove is 3 to 10 cm, and the width of the top surface of each groove is 3 to 10 cm.

The through holes are large through holes, the cross section of each through hole is a rectangle, the cross section area of the through hole in each transverse groove is 100 cm², and the cross section area of each through hole in the longitudinal groove is 390 cm². The through holes are in communication with each other.

The preparation method is the same as that for Embodiment 2.

The grooves are provided with cover plates by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling of phenomena of the anode carbon block occurs.

Embodiment 5

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 25, the A-A sectional structure is shown in FIG. 26, the B-B sectional structure is shown in FIG. 27, the C-C sectional structure is shown in FIG. 28, the D-D sectional structure is shown in FIG. 29, and the E-E sectional structure is shown in FIG. 30. The structure is the same as that of Embodiment 1, but the difference is that: Each transverse groove is provided with one through hole in communication with the corresponding trench, and the longitudinal groove is provided with four through holes in communication with the corresponding trench.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, the height of each groove is 3 to 10 cm, and the width of the top surface of each groove is 3 to 10 cm.

The through holes are large through holes, the cross section of each through hole is a rectangle, the cross section area of the through hole in each transverse groove is 100 cm², and the cross section area of each through hole in the longitudinal groove is 300 cm².

The preparation method is the same as that for Embodiment 1.

The grooves are provided with cover plates by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 6

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 31, the A-A sectional structure is shown in FIG. 32, the B-B sectional structure is shown in FIG. 33, the C-C sectional structure is shown in FIG. 34, the D-D sectional structure is shown in FIG. 35, and the E-E sectional structure is shown in FIG. 36. The structure is the same as that of Embodiment 1, but the difference is that: The bottom of each transverse groove is provided with two through holes which are in communication with the trench corresponding to this groove. The longitudinal groove is provided with four through holes which are in communication with the corresponding trench.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, the height of each groove is 3 to 10 cm, and the width of the top surface of each groove is 3 to 10 cm.

The through holes are large through holes, and the cross section of each through hole is a rectangle with an area of 50 cm².

The preparation method is the same as that for Embodiment 2.

The grooves are provided with cover plates by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 7

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 37, the A-A sectional structure is shown in FIG. 38, the B-B sectional structure is shown in FIG. 39, the C-C sectional structure is shown in FIG. 40, the D-D sectional structure is shown in FIG. 41, and the E-E sectional structure is shown in FIG. 42. The structure is the same as that of Embodiment 6, but the difference is that: The three crossing points of the three transverse grooves respectively with the longitudinal groove are respectively provided with a small through hole, and the cross section of each small through hole is a circle with an area of 11 cm².

The preparation method is the same as that for Embodiment 1.

The grooves are provided with cover plates by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 8

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 43, the A-A sectional structure is shown in FIG. 44, the B-B sectional structure is shown in FIG. 45, the C-C sectional structure is shown in FIG. 46, the D-D sectional structure is shown in FIG. 47, and the E-E sectional structure is shown in FIG. 48. The edges of the top surface of the anode carbon block 1 are provided with chamfers, two rows of carbon bowls are uniformly distributed on the top surface, and each row of carbon bowls are longitudinally arranged along the anode carbon block and consist of four carbon howls 2. A groove 3 is formed among the carbon bowls, the bottom of the groove is provided with a through hole 4 which is in communication with a trench 5 in the bottom of the anode carbon block, and a cover plate 6 is arranged above the groove.

The groove is a longitudinal groove between the two rows of carbon bowls. The trench is formed in the bottom of the anode carbon block in a position corresponding to the groove. The bottom of groove is provided with one through hole which is in communication with the trench.

The axis of the longitudinal groove runs parallel to the axis of the anode carbon block. The longitudinal groove is in the middle of two adjacent rows of carbon bowls, and both ends of the longitudinal groove extend to the chamfers of two short edges.

The top of the trench is 20 to 50 cm below the top of the anode carbon block, the bottom of the trench is in communication with the bottom of the anode carbon block, and the width of the trench is 2.5 to 3.5 cm.

The cross section of the groove is an inverted triangle, the height of the groove is 3 to 10 cm, and the width of the top surface of the groove is 3 to 10 cm.

The longitudinal axis of the through hole is vertical to the bottom surface of the anode carbon block.

The through hole is a large through hole, and the cross section of the through hole is a rectangle with an area of 390 cm².

The preparation method is the same as that for Embodiment 2.

The groove is provided with a longitudinal cover plate by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 9

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 49, the A-A sectional structure is shown in FIG. 50, the B-B sectional structure is shown in FIG. 51, the C-C sectional structure is shown in FIG. 52, the D-D sectional structure is shown in FIG. 53, and the E-E sectional structure is shown in FIG. 54. The, structure is the same as that of Embodiment 2, but the difference is that:

The bottom of each groove is provided with one through hole which is in communication with the trench corresponding to this groove.

The top of each trench is 20 to 50 cm below the top of the anode carbon block, and the width of each trench is 2.5 to 3.5 cm.

The cross section of each groove is an inverted triangle, the height of each groove is 3 to 10 cm, and the width of the top surface of each groove is 3 to 10 cm.

The through holes are large through holes, and the cross section of each through hole is a rectangle with an area of 100 cm².

The preparation method is the same as that for Embodiment 1.

The grooves are provided with transverse cover plates by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Embodiment 10

The sectional structure of the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is shown in FIG. 55, the A-A sectional structure is shown in FIG. 56, and the C-C sectional structure is shown in FIG. 57. The edges of the top surface of the anode carbon block are provided with chamfers, a row or two rows of carbon bowls 2 are uniformly distributed on the top surface, and each row of carbon bowls 2 are longitudinally arranged along the anode carbon block 1 and consist of four carbon bowls 2. A groove 3 is formed among the carbon bowls 2, and the bottom of the anode carbon block 1 is provided with a trench 5. The bottom of the groove 3 is provided a through hole 4 which is in communication with the trench 5, the length of the through bole 4 is equal to the length of the anode carbon block 1, the through hole is in communication with the trench 5, and the anode carbon block is longitudinally divided into two identical small anode carbon blocks.

The groove is a longitudinal groove located between the two rows of carbon bowls.

The top of the trench is 40 cm below the top of the anode carbon block, and the width of the trench is 3 cm.

The cross section of the groove is an inverted triangle, the height of the groove is 6 cm, and the width of the top surface of the groove is 6 cm.

The width of the groove is the same as that of the trench, the length of the groove is 150 cm, and the cross section area of the groove is 450 cm².

The preparation method comprises: preparing a green body of the anode block by a vibration molding method, and the lower surface of the upper weight dropper in a compression mold is provided with a corresponding bump; preparing carbon bowls, a groove and a deep hole with a depth of 40 cm and with the same length as that of the anode carbon block in the green body of the anode carbon block during vibration molding; after demolding and cooling down, putting the green body of the anode carbon block into a roasting furnace and roasting to 1100 to 1300° C. to prepare a roasted body of the anode carbon block with carbon bowls, a deep hole and a groove; and then physically cutting out the trench in the bottom of the roasted body of the anode carbon block and making the trench be in communication with the deep hole to divide one anode carbon block into two small anode carbon blocks, thus the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is prepared. The groove is provided with a transverse cover plate by the same method as that for Embodiment 1.

It is proved by testing that the tank voltage is reduced by using the anode carbon block, the gas produced by an anode is smoothly and uniformly discharged, the influence of gas escape on fluctuation of cathode molten aluminum is obviously reduced, and no falling off phenomena of the anode carbon block occurs.

Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. 

What is claimed is:
 1. An aluminum electrolytic tank anode carbon block of an irregularly-shaped structure with an exhaust passage, edges of a top surface of the anode carbon block provided with chamfers, a row or two rows of carbon bowls uniformly distributed on the top surface, and each row of carbon bowls longitudinally arranged along the anode carbon block and consisting of 3 to 5 carbon bowls, wherein grooves are formed among the carbon bowls, and a bottom of the anode carbon block is provided with trenches; a bottom of each groove is provided with through holes which are in communication with the trenches in the bottom of the anode carbon block.
 2. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein a row of carbon bowls are arranged on the top surface of the anode carbon block, a transverse groove is formed between every two adjacent carbon bowls; or two rows of carbon bowls are arranged on the top surface of the anode carbon block, a longitudinal groove is formed between the two row of carbon bowls, or a transverse groove is formed between every two adjacent carbon bowls in the same row, or these two kinds of grooves coexist.
 3. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein the trenches are in the bottom of the anode carbon block in positions corresponding to each groove, the bottom of each groove is provided with at least one through hole which is in communication with the trench corresponding to the groove.
 4. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 2, wherein an axis of the transverse groove is vertical to the longitudinal axis of the anode carbon block, the axis of the transverse groove is in a middle of two adjacent carbon bowls in the longitudinal direction of the anode carbon block, and both ends of the transverse groove extend to the chamfers of two long edges; the axis of the longitudinal groove runs parallel to the axis of the anode carbon block, the longitudinal groove is in the middle of two adjacent rows of carbon bowls in the longitudinal direction of the anode carbon block, and both ends of the longitudinal groove extend to the chamfers of two short edges.
 5. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein the top of each trench is 20 to 50 cm below the top of the anode carbon block, the bottom of each trench is in communication with the bottom surface of the anode carbon block, and the width of each trench is 1.0 to 3.5 cm.
 6. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein a cross section of each groove is an inverted isosceles triangle or an inverted isosceles trapezoid, and a height of each groove is 3 to 10 cm, when the cross section of each groove is an inverted isosceles triangle, the width of the top surface of each groove is 3 to 10 cm, when the cross section of each groove is an inverted isosceles trapezoid, the width of the top surface of each groove is 5 to 10 cm, and the width of the bottom surface is 3 to 8 cm.
 7. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein the through holes are in the bottom of each groove, and the longitudinal axis of each through hole is vertical to the bottom surface of the anode carbon block.
 8. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein the through holes include small through holes and large through holes, the cross section of each small through hole is circular, oval., square or rectangular, with an area of 3 to 18 cm²′ when the cross section of the small through hole is square or rectangular, four corners of the square or rectangle are filleted corners, the cross section of each large through hole is rectangular, with an area of 18 to 500 cm².
 9. The aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, wherein when a length of each through hole is equal to the length of the anode carbon block, the through holes are in communication with the trenches, and one anode carbon block is longitudinally divided into two identical small anode carbon blocks.
 10. A preparation method for the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage of claim 1, the method comprising: preparing a green body of the anode carbon block by a vibration molding method or a compression molding method; when the vibration molding method is used, the lower surface of the upper weight dropper in a vibration mold is provided with corresponding bumps; when the compression molding method is used, the lower surface of the upper mold core in a compression mold is provided with corresponding bumps; preparing carbon bowls, grooves and deep holes with a depth of 20 to 50 cm in the green body of the anode carbon block during vibration molding or compression molding; after demolding and cooling down, putting the green body of the anode carbon block into a roasting furnace with 1100 to 1300° C. to prepare a roasted body of the anode carbon block with carbon bowls, deep holes and grooves in the top; and physically cutting out the trenches in the bottom of the roasted body of the anode carbon block and making the trenches be in communication with the deep holes or a groove-shaped passage to form the through holes, thus the aluminum electrolytic tank anode carbon block of the irregularly-shaped structure with the exhaust passage is prepared, the corresponding bumps refer to the bump structures corresponding to the positions of the carbon bowls, grooves and through holes in the anode carbon block. 